Television



Oct. 7, 1930. c. D. FAHRNEY TELEVISION 4 Sheets-Sheet l Filed March 13 x x x x x x ATTDRNEQ Oct. 7, 1930. c. D. FAHRNEY 1 ,777,556

TELEVI S I ON Filed March 13, 1929 4 Sheets-Sheet 2 fill T S Y mil Y LI TTDR E Oct; 7, 1930.

C. D. FAHRNEY TELEVI S ION Filed March 15, 1929 4 SheetS-Sheet .fTTEIRNELF C. D. F'AHRNEY TELEVI S ION Filed March 13, 1929 4 Sheets-Sheet 4 A'fTD N Eu Patented Oct. 7, 1930 UNITED STATES PATENT OFFICE CALLO D. -F.A.HRNEY, F CAMBRIDGE, MASSACHUSETTS 'rnnnvrsroir Application filed March 18, 1929. Serial No. 346,689.

and be clearer, and generally more pleasing,

than is possible with the systems now in use, and in which the picture-receiving surface and the scanning member or members are so related that the picture may conveniently be viewed by an observer irrespective of the position of the apparatus. Other objects of the invention are to provide an extremely simple televisor which shall be economical in construction and eflicient in operation. Further objects of the invention will herein after appear in the detail description of the specific embodiments thereof.

With the foregoing objects in view my invention contemplatesthe use of .a magnifying mirror s a picture-receiving surface, either alone r in combination with another magnifying mirror, or else a plane surface upon which the picture is reflected from the mirror first mentioned and from which it is reflected to the eye of the observer.

- My invention contemplates also the use of a scannin memberwhich is'inclined to the horizonta or else has its eifective area so inclined that the picture may readily be seen by an observer located above the apparatus.

My invention contemplates also, and consists of, the parts and combination of parts hereinafter more fully described and set forth in the appended claims.

My invention may best be understood by having reference to the'drawin s which accompany and form a part. of t is specification in whicha y Figure 1 is a vertical section of a television- ,receiving apparatus embodying my inven Fig. 2 is a front elevation partly irl'section of said apparatus; I

Fig. 3 is a central section showing a modification of the scanning disc;

Fi 1: is a central section of a further modification in which two cooperating scanning members are emp y d;

Fig. 5 is a front view ofthe apparatus shown in Fig. 4;

Fig. 6 is a fragmentary sectional View of a further modification in which the co-operating scanning members are shown as cones; A

Fig. 7 1s a fragmentary sectional view of another modification in which the lam is placed on the outside of scanning mem ers of the type shown in Fig. 6;

, Fig. 8 is a central section of a modified form of television-receiving apparatus embodying my invention;

Fig. 9 is afragmentary sectional view of the apparatus shown in Fig. 8, provided with two magnifying mirrors.

In the particular drawings selected for more fully disclosing the principle of my invention, 10 is a motorof any suitable type mounted on the shaft of which is a scanning disc 11 provided with a series of perforations 12 arranged in the form of a spiraI and through which light from the lamp 13, the luminosity of which is varied by the received current, is projected to the concave or magnifying mirror 14. On the casing 15 enclosing the motor and its associated parts are mounted the said lamp 13 by the depending bracket 16 and the mirror 14 by the adjustable bracket 17. The motor rotates the scanning disc insynchronism with the analyzing disc at a transmitting station in the manner well understood and the picture surface of the mirror and clears the top of the scanning disc and lamp, whereas ifsaiddisc were rotated in a vertical plane the observer would have to move to a higher position in order to see the entire picture.

Howeverpit is not' absolutely essential to. incline the shaft and the disc because, as shown in Fig. 3, the shaft 19. may be horizontal and the effective or outer perforated ries of radial slots 24, the arrangement being that the ends of each ar'cuate slot terminates at the inner and outer ends of two of the contiguous co-operating radial slots, and therelative rotational speeds of the two discs is such that each radial slot is swe t by an 'arcuate slot'during the time that sald radial slot moves a distance equalto its own width. The member 23 is rotated by the gears 24, 25 and 26, the latter being mounted on the shaft 27, and by the pinion 28 on said shaft and the annular gear 29 which meshes with said pinion and supports the disc 23. The motor being in synchronism with an appropriate analyzing apparatus at the transmit- .ting station, the light transmitted through two co-operating slots 22, 24 from the lamp 13 impinges on the magnifying mirror 30 whence it is reflected to the magnifying mirror 31 in which the picture may be seen by.

the observers, one of which is indicated as having his eye at the point 32.

I have found in actual practice that when two such magnifying mirrors are employed, a better, more .pleasing and more detailed picture can be formed than when a single picture-receiving surface is used.

In the modification shown inFig. 6, the inclined shaft 34 carries the-scannin member 35 which preferably is a sur ace of revolution of any suitable shape and is shown'in the present instance as a cone provided with a plurality of rows of perforations 36, each row being arranged along a generatrix'of said cone, and said perforations being disposed around said cone in such manner as to form a plurality of spirals,

herein shown as four. The co-operating cone 37 is carried loosely on the shaft 34 and is provided with a plurality of slots 38 arranged to co-operate successively with said perforations, and each extending approximately one-half way around the periphery of said member in a diagonal direction. Gearing such as shown in Fig. 4 rotates the outer cone 37 at approximately one-eighth the speed of the inner perforated cone. Light in various degrees of luminosity, depending on the variations of the received current, is transmitted from the lamp 13 to the concave or magnifying mirror 39 whence it was reflected -to the plane mirror 40 so that the-picture may be viewed by a number of observers, the eye of one of which is indicated at 41.

In the modification shown in Fig. 7 the construction is identical with that of Fig.

6,.except that the lamp 13 is placed outside the co-operating scanning members and the magnifying mirror 42 is located inside the same at the appropriate angle to receive the picture which may be viewed by a number of observers, the eye of one of whom is indicated at 43. v p

In Figs. 6 and 7 the shaft 34 and also the effective portions of the scanning members are inclined to the horizontal so that as above explained with respect to Fig. 1, an observer locatedabove the apparatus may conveniently view the picture.

As will be obvious, it is sometimes desirable to have the televisor located below theplane of the observers eye and accordingly, y means of the present invention, the observer may "see the picture without incon- VBIHQIICG.

In Fig. 8 the magnifying mirror 44 is so I placed with respect to the ap aratus that the picture may be viewed by 0 servers stationed above said apparatus, the eye of an observer being indicated at 45. The gear- .ing whereby the scanning members 35, 37

are rotated at the proper relative speeds is identical with that shown in Fig. 4 and the construction of said members is the same as above described in connection with Fig. 6.

In the modification illustrated in Fi .9, the construction of the scanning mem ers and their driving mechanism is identical with that shown in Fig. 8. The picture formed on the magnifying mirror 44 is reflected to the magnifying mirror 46 and may be seen by observers, theeye of one of whom is indicated at 47. In the arrangements of Figs. 8 and 9, the drive shaft and the effective surfaces of the scanning members are inclined to the horizontal so that as explained in connection with Fig.1, the observer may conveniently view the picture formed by a televisor apparatus located beneath him.

Having thus described illustrative embodiments of my invention, without however limiting the same thereto, what I claim and desire to secure by Letters Patent is 1. A television receiving apparatus com prising in combination a scanning member having its effective area inclined to the horizontal, and a magnifying mirror associated therewith, as a picture-receiving surface. 7

2.'A television receiving apparatus comprising in combination a scanning member, a lamp associated with said scanning member, a magnifying mirror so'related to said mem,- ber and lamp that light transmitted through said scanning member will impinge on said mirror, and a picture-receiving surface so arranged with respect to said mirror that the picture formed on the latter is reflected to said surface.

3. A'television receivingapparatus comprising in combination a scanning member,

a magnifying mirror so related to said member and lamp that light transmitted through. said scanning member will impinge on said mirror, and aseeond magnifying mirror so 5 related t0 the mirror first mentioned that the picture formed on the latter is reflected on said second magnifying mirror.

In testimony whereof, I have hereuntb subscribed my name this 11th day of March,

GALLO D. FAHRNEY. 

